Byte Converter: KB, MB, GB, TB Calculator Free

Free byte converter to calculate between bits, bytes, KB, MB, GB, TB, and PB. Supports both decimal and binary units. Convert digital storage sizes instantly.

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Understanding Digital Storage Units

Digital storage is measured in bytes — a byte is 8 bits, and each bit is a single 0 or 1 in binary. From there, units scale up by factors of 1,000 (decimal) or 1,024 (binary).

Decimal vs Binary Units

There are two competing standards for measuring digital storage, and the difference matters:

Decimal (SI)Binary (IEC)Difference
1 kB = 1,000 bytes1 KiB = 1,024 bytes2.4%
1 MB = 1,000,000 bytes1 MiB = 1,048,576 bytes4.9%
1 GB = 1,000,000,000 bytes1 GiB = 1,073,741,824 bytes7.4%
1 TB = 1,000,000,000,000 bytes1 TiB = 1,099,511,627,776 bytes10%

This is why a “1 TB” hard drive shows up as ~931 GiB in your operating system — the manufacturer uses decimal, but your OS reports in binary.

Common Byte Conversions

Decimal Scale

UnitBytesAbbreviation
Kilobyte1,000kB
Megabyte1,000,000MB
Gigabyte1,000,000,000GB
Terabyte1,000,000,000,000TB
Petabyte1,000,000,000,000,000PB

Quick Conversions

1 GB = 1,000 MB
1 TB = 1,000 GB
1 PB = 1,000 TB

1 byte = 8 bits
1 MB = 8 Mb (megabits)

The lowercase b means bits, uppercase B means bytes. Internet speeds are usually measured in megabits per second (Mbps), while file sizes are in megabytes (MB). To convert: 100 Mbps = 12.5 MB/s.

How Much Storage Do You Need?

Content TypeAverage SizeFiles per GB
Text document50 kB20,000
High-res photo5 MB200
MP3 song4 MB250
1080p video (per min)150 MB~7 min
4K video (per min)400 MB~2.5 min

Storage Planning Example

Planning storage for a photography project:

Photos per shoot = 200
Average photo size = 25 MB
Shoots per month = 4

Monthly storage = 200 × 25 MB × 4 = 20,000 MB = 20 GB
Annual storage = 20 GB × 12 = 240 GB

Free Byte Converter

Convert between bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and more — both decimal and binary units.

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Example

How many megabytes in 2 TB?

2 TB = 2 × 1,000 GB = 2,000 GB
2,000 GB = 2,000 × 1,000 MB = 2,000,000 MB

Frequently Asked Questions

How many megabytes are in a gigabyte?

In the decimal (SI) standard used by storage manufacturers, 1 GB = 1,000 MB. In the binary (IEC) standard used by operating systems, 1 GiB = 1,024 MiB. The decimal standard is more common in everyday use, but the binary standard reflects how computers actually address memory.

Why does my hard drive show less space than advertised?

Hard drive manufacturers use the decimal standard (1 GB = 1,000,000,000 bytes), while operating systems typically report in binary (1 GiB = 1,073,741,824 bytes). A “1 TB” drive contains 1,000,000,000,000 bytes, which equals approximately 931 GiB — the number your OS displays.

What is the difference between Mbps and MB/s?

Mbps (megabits per second) measures network speed, while MB/s (megabytes per second) measures data transfer rate. Since 1 byte = 8 bits, divide Mbps by 8 to get MB/s. A 100 Mbps internet connection downloads at about 12.5 MB/s in ideal conditions.

For converting between number bases used in computing, check our hex to decimal converter. For other unit conversions, see the unit converter.

Convert Data Units in Notes Calculator

Notes Calculator supports both decimal and binary digital storage units:

# Storage Planning
photo size = 5 MB
photos = 10000
total = photo size * photos
total in GB

// Binary units
1 TB in GiB
1024 KiB in MiB

// Network speed to transfer rate
internet speed = 100 Mb
internet speed in MB

// How long to download a file?
file size = 4 GB
file size in Mb

The app distinguishes between bits (b, kb, Mb, Gb) and bytes (B, kB, MB, GB), and supports binary units (KiB, MiB, GiB, TiB) alongside decimal ones. Variables let you plan storage needs interactively — change photos and see the total update in real time.

Try it in Notes Calculator

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